Compounded hydrocarbon oil



' Patented Dec. 11, 1945 by mesne assignments, to California ResearchCorporation, San Francisco, Calii'., a corporation of Delaware NoDrawing. Application March 15, 1943,

' Serial No. 479,260

(Cl. 252-42.'l)

12 Claims.

This invention relates to a new and useful composition of matter andinvolves a composition comprising a hydrocarbon oil and a newcombination of stabilizing ingredients.

This application is a continuation-in-part of Genoils to obtain desiredcharacteristics involves empirical phenomena, and the action of untestedcombinations or different types of compounding agents cannot bepredicted.

A characteristic which has been the subject of extensive investigationis the tendency of hydrocarbon oils to deteriorate or partiallydecompose and oxidize when subjected to high temperatures. Thisdeterioration is evidenced by the deposition Of adhesive deposits on hotmetal surfaces over which the hydrocarbon oil may flow. It is importantthat resistance to such deterioration be imparted to hydrocarbon oils,particularly to lubricating oils, in order that such compositions may berelatively free from the tendency to form such deposits even under hightemperatures and severe operating conditions. A direct result of thistype of deterioration during lubrication of internal combustion engines,such as engines of the Diesel type, is the. tendency of the'oil to causeor permit the sticking of piston rings.

The crankcase lubricant in internal combustion engines is subjected toextremely severe operating conditions, and in engines of the Diesel typethe lubricant encounters in the piston ring zone temperatures of fromapproximately 425 to 650 F. and pressures from the oxidizing combustiongases as high as 750 to 1150 pounds per square inch. In its morespecific aspects the present invention is directed to the improvement ofhydrocarbon lubricating oils by imparting thereto increased resistanceto deterioration by heat at h temperature levels in the order of thoseabove mentioned. 1 v

We have discovered that aromatic compounds having at least two polarsubstituents on the aromatic nucleus, when used in combination withmetal phenates, impart to hydrocarbon lubricating oils 9. number ofhighly desirable properties and improve the lubrication and operation ofinternal combustion engines. More particularly, it has been discoveredthat a lubricating oil containing both ametal phenate and a polypolarsubstituted aromatic compound having antioxi dant properties permitslonger periods of operation of engines without the necessity of majoroverhauls heretofore occasioned by stuck pistons, wear of pistons andcylinder walls, or corrosion of bearing metal alloys.

The broader aspects of the invention involve the discovery thatpolypolar substituted aromatic compounds and metal phenates cooperate togive new results in hydrocarbon oil compositions. Hydrocarbon oilscontaining this combination of ingredients have greater stability undervarious operating conditions than do oils containing either of thesetypes of ingredients alone. For example, the same stability is notobtainable with 1% of a metal salt of a phenol or with 1% of thepolypolar aromatic antioxidant in a lubricating oil as is obtained withof the metal phenate and /4,% of the antioxidant in the same lubricatingoil.

Metal phenates, which may be added to hydrocarbon oils such as minerallubricating oils to provide one component of the new composition ofmatter herein claimed, compris the alkali, al-- kaline earth and othermetal phenates. Examples of such metal phenates are sodium phenates,potassium phenates, beryllium phenates, calcium phenates. strontiumphenates, barium phenates, magnesium phenates, zinc phenates, cadmiumphenates and aluminum phenates.

The metal phenates are preferably formed from high molecular weightphenols oi the type formula:

in which u, v, w, a: and y are'selected from the group consisting ofhydrogen, hydrocarbon, oxy and hydroxy radicals. The phenol preferablycontains at least one alkyl group having at least four carbon atoms. Theterm hydrocarbon radicals used in the above connection is intended toinclude alkyl, aryl, alkaryl, aralkyl and cyclic non-benzenoid groups;and the term oxy radicals refers to a group in which the hydrogen of ahydroxy radical has been replaced by esteriilcation, neutralization, orthe like. Although phenols containing at least one alkyl substituent arepreferred, the invention does not preclude compounds containing no alkylgroups and embodies the substitution of aryl, alkaryl, aralkyl andcyclic non-benzenoid groups as well as conjugated rings in the aromaticnucleus to which the phenolic hydroxy group is directly attached.

Examples of specific metal phenates which may be utilized comprisesodium lauryl phenate, sodium cetyl phenate; calcium lauryl phenate,calcium cetyl phenate, calcium'di-amyl phenate, calcium heptyl phenate,calcium p-tertiary amyl phenate, calcium monochloramyl phenate, calciump-cyclohexanol phenate; aluminum lauryl phenate, aluminum di-cetylphenate; magnesium cetyl phenate, barium cetyl phenate; and calciumcetyl cresylate. The metal phenates of this invention may be prepared byany suitable method. For example, the alkyl phenols may be obtained byalkylation of the phenols, in the presence of sulfuric acid,

with an olefin or an olefin polymer, such as di, tri

and tetra butylenes or di, tri and tetra isobutylenes. The alkylatedphenol may then be reacted with the proper metal or metal ion, or thesodium or potassium salts of the alkyl phenol may be reacted with theproper metal ion to obtain the desired salt. The preparation of themetal phenates comprises no part of this invention and may be effectedby those skilled in the art without undue difficulties.

Among the polypolar substituted aromatic compounds that may be used inaccordance with the invention are the polyhydroxy phenols. aryldiai'nines, nuitrosoamines, oxazines, benzothiazole and phenthiazine.

The polar substituted aromatic compounds used in combination with ametal phenate in accordance with the invention have, as stated, at leasttwo polar substituents, and are herein frequently referred to forconvenience as polypolar substi- 4 tuted aromatic compounds" and as"polypolar compounds. These substituents may be attached to the samearomatic nucleus or totwo or more different aromatic nuclei (as indiphenyl) but preferably at least two polar groups are attached to asingle aromatic nucleus.

The following polar groups will serve toexemplify the typeset polarsubstituents that may be present:

--OH Hydroxyl OR Alkoxy1 (aroxyl, cycloalkoxyl) --NH:

NHR Amino (including substituted amino) NR1R2 I -NO Nitroso CO....Carbonyl -CO-R Keto '--CHO Aldehydo COOH Carboxyl --COOR.. Carboxy esterCONH:-- Amido SH. Mercapto SR Allwl thio (aryl thio, cycloalkyl thio) C1Chloro Br Bromo Preferably, aromatic compounds are used which,

substituted amino), nitroso, nitro, mercapto. and organic substitutedmercapto substituents. One or more of the polar substituents may formpart of a ring, as in the benzothiazoles and phenthiazlnes. Preferably,the polar groups are directly connected to the aromatic nucleus, thatis, are nuclear substituents, but one or more of the polar groups may beseparated from the aromatic nucleus by one or even two carbon atoms.Thus, saligenin (ortho hydroxy benzyl alcohol) may be used, butpyrocatechin (1,2-dihydroxy benzene) is preferred.

In the table below are illustrated the preferred classes of polypolarsubstituted aromatic compounds. specific members of these classes, andthe structures of these specific members:

Class of compounds Specific members Polyhydric phenols OH p-HydroquinoneAryl polyamiues '13,

2, i-diamino toluene Aminophenols 0 p-Amino phenol Nitroso and nitroamines N(CH'1)1 0H and phenols.

N 0 N 0 p-Nitrooo mm honol dlmcthylanilino p. p

Polar substituted aryl carboxyestcrs. COOCH; COOK:

Methyl anthrr Methyl lalicylate niiato v Phenuines, phcnomines. N 0

phenthiuines and bemothiaaoles.

Phonaaine Phcnoxuine 8 B\ (I p l (1 Phenthiuina Mercambcmo- As has beenpreviously pointed out. the present invention embraces the discoverythat hydrocarbon oils containing both the metal salt of a phenol and apolypolar substituted aromatic compound have new and unpredictableadvantages. The properties of hydrocarbon oils containing both a metalphenate and a polypolar compound are illustrated by the followingdiscussion and data.

The strip corrosion test referred to in the table below was carried outas follows: Glass tubes 2 inches in diameter and 20 inches long wereimmersed in an oil bath, the temperature of which was automaticallycontrolled to within plus or minus 1 F. of the test temperature, whichwas 300 F. Approximately 300 cc. of oil under test was placed ineachtube and air was bubbled through it at the rate of 10 liters perhour. Strips of the different types of bearing metal were placed in theoils; in most cases the copper-lead and noted in the table below alongwith the corrosion results.

The base oil was an SAE 30 solvent treated Pennsylvania (parailinic) oiland the calcium cetyl phenate was the normal calcium salt of analkylated phenol produced by alkylating phenol in the presence ofsulfuric acid with a butylene polymer averaging Cm per molecule (fourbutylene units), separating the alkylated phenol and forming the calciumsalt.

desired. As little as 0.05% by weight of various oi the polypolarcompounds gives measurable improvements, particularly as respects thecolor stability of'the compounded oil. From approximately 0.1% to 2% ofthe compound may be added to lubricants containing metal phenates wherestability at high temperature comprises the principal property desired.Solutions containing more than 2% of the compounds in mineral oils maybe utilized for various purposes, e. g., for preparing lubricatinggreases and concentrates capable of dilution with lubricating oils andthe like. Likewise, the proportion of metal phenates present incompounded lubricants may vary widely depending on the uses involved andthe properties desired. As little as 0.1% by weight of the phenate givesmeasurable improvement, although from approximately 0.25% to BP-proximately 2% phenate is'preferred'where' the compounded oil is to beused as a crankcase lubricant for internal combustion engines. As muchas or more'by weight of various of the phenates may be dissolved inmineral oil for the purpose of preparing a concentrate capable ofdilution with lubricating oils and the like. Concentrates containinghigh percentages of the phenate and a polypolar compound comprise aconvenient method of handling the ingredients and may be used asaddition agents for lubricents in general as well as for other purposes.

The combination of ingredients of this invention may be present inhydrocarbon oils containing other compounding agents such as pour pointdepressants, oiliness agents, extreme pressure addition agents, bloomingagents and compound for enhancing the viscosity index of the hydrocarbonoil. The invention in its broader aspects Strip corrosion test Used oilinspections Base oil Additives Cu-Pb, hours Cd-Ag, hours viscosity (SSU)Neum increase at F ization 24 48 72 24 48 72 at 100 F. number Penn. BAE30". Nil 1.9 6.0 22.0 0.0 0.2 0.2 88 5.2 1.39 Do 0.5% Ca cetyl phenate12. 6 52. 1 100. 5 1. 1 20. 1 103. 5 159 7. 3 1. m (l,% ;i-hdroqunronfi. hi i jnnfain- 5. 5 13.9 60.5 0. 2 0. 3 0.3 135 5. 2 1. l3

.5 0 a cety ena a py oqulnone "P 0. 0 0. 3 0.5 0.0 0.2 0. 1 141 8. 10.84 1% diamino toluene 0. 2 +1. 7 +1. 1 +0. 1 +0. 1 +0. 1 2. 2 0.540.6% Ca cetyl phenolic-{4% dmmlno toluene +0. 5 0. 5 1. 2 0. 0 0. 0 0. 062 2 3 0. 23 1% nitrosodlmethylanfllne 3. 3 3. 2 3. 4 0. 0 0. 0 0. 0 662. 4 0. 2) 0.5 0 Ca cetyi phenate+1% p-nitrosodimethylanilin 5. 6 9. 815. 8 0. 3 0. 2 0. 2 83 4. 7 0. 20 1% methyl anthranilute 1..-. 0. 9 2.4 10. 3 0.1 0. 2 0. 2 111 4. 2 1. 70 0.5% Ca cetyl phenate+1% methylanthraniiate 1. 1 1. 0 22 0 0. 0 0. 0 20. 9 01 4. 3 0. 72 Il)%7mtacaptgblenzliaathiizzeolel t.-. 3. 2 3. 2 3. 2 0. 0 0. 0 0. 0 140 2.0 0. 01

.5 v a ee one o more: 0-

benzo Zia? "2 6.5 0.3 0.5 0.1 0.1 0.1 183 5.7 0.3 1% n 1.8 1.8 2.0 0.21.5 1.0 122 8.0 0.75 0.5% Ca cetyl phenute+1% phenthiuine. 6. 3 32. 094. 7 2. 8 31. 6 $1. 1 131 0. 0 0. 81

Besides the above indicated and other advantages possessed by thecombination in hydrocarbon lubricating oils or metal salts of phenolsand the polypolar substituted aromatic compoimds oi the invention, agiven amount or the combination also imparts to such oils a greaterstability against oxidation than is imparted by an equal amount ofeither componentalone. a

A variety of base, oils may be employed for embraces mineral hydrocarbonoils containin in addition to the metal phenate and the polypolarcompound; thickening agents and/or metal soaps in grease-formingproportions or in amounts incompounding with the additives of thisinvention; e. 3., parafllnic, naphthenic and mixed base oils. Y

The pr ortion of polypolar substituted aromatlc compound which may beadded to mineral lubricatini oils, according to the principles of thepresent invention, may vary widelydependingupontheuseainvolvedandthepropertlfl sumcient to form grease, asin the case of mineralcaster machine oils or other compounded liquidlubricants.

Aeusedinthe ap'pendedclaimatheterma.

amine and amino? unless otherwise qualified.

described in detail and numerous examples of the composition given, thishas been done by way of illustration only and with the intention that nolimitation should be imposed on the invention thereby. It will beapparent to those skilled in the art that numerous modifications andvariations of the illustrative examples may be efiected in the practiceof the invention which is of the scope of the claims appended hereto.

We claim:

1. A lubricant comprising a major proportion of a hydrocarbonlubricating oil and a small amount each, sufllcient to stabilize the oilagainst tion inhibitor containing a benzene nucleus towhich are directlyattached at least two-substituents selected from the group consisting atamino radicals and oxy radicals. 3. A liquid lubricant comprising amajor proportion of a hydrocarbon lubricating 011, about 0.1 to 2% byweight based on the oil of an oilsoluble polyvalent metal salt of -analkylated phenol and about 0.05 to 2% by weight based on the oil of anaromatic compound containing a benzene nucleus to which are directlyattached a plurality of oxy radicals. 1

4. A liquid lubricant comprising a major proportion of a petroleum oilof lubricating viscosity,

, about 0.25 to 2% by weight based on the oil of a poiyvalent metal salt02 a phenol and about 0.05 to 2% by weight based on the oil of anoxidation inhibitor which is an aromatic compound containing a benzenenucleus to which are directly attached a plurality oi substituentsselected from the group consisting of amino substituents and onsubstituents.

5. A liquid lubricantcomprisin'g a major proportion oi a petroleumlubricating oil and containing about 0.25 to 2% by weight based on theoil of an oil-soluble alkaline earth metal salt of an alkylated phenoland about 0.05 to 2% by weight based on the oil of a polyhydric phenol.

6. A lubricant comprising a major proportion of a petroleum lubricatingoil containing about 0.25 to 2% by weight based on the oil of anoilsoluble alkaline earth metal salt of an alkylated phenol and about0.1 to2% by weight based on the oilof an aryl polyamine.

'I. A liquid lubricant comprising a major proportion ot a hydrocarbonlubricating 011, about 0.1 to 2% byweight of an oil-soluble polyvalentmetal salt of an alkylated phenol and about 0.1 to 2% by weight of anaromatic compound containing in the aromatic nucleus at least two aminosubstituents.

8. The lubricant or claim 7 whereinsaid aromatic compound is an aryldiamine. y

9. The lubricant of claim 4 wherein said polyvalent metal is an alkalineearth metal.-

10. The lubricant of claim 4 wherein said polyvalent metal is calcium.

11. A concentrated dispersion in viscous hydrocarbon oil oi a metalphenate and an oxidation inhibitor which is an aromatic compoundcontaining a benzene nucleus towhich are directly attached a pluralityof substituents'. selected from the group consisting 01 aminosubstituents and oxy substituents. r

12. A liquid lubricant comprising a major proportion of a hydrocarbonlubricating oil, about 0.1 to 2% by weight based on the oil of anoilsoluble polyvalent metal salt of an 'alkylated phenol and about 0.05to 2% by weight based on the oil of an'aromatic compound containing abenzene nucleus to which are directly attached 'two hydroxyl radicals.

FRANK W. KAVANAGH. BRUCE B. FARRINGTON. JAMES O. CLAYTON.

